How severe is CVE-2020-26100?

CVE-2020-26100 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-26100 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26100?

CVE-2020-26100 affects Cpanel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-26100?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-26100 published?

CVE-2020-26100 was published on 2020-09-25 and last updated on 2026-06-17.

CVE-2020-26100

CVE-2020-26100 is a critical-severity vulnerability in Cpanel with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Cpanel
Published: 2020-09-25
Last modified: 2026-06-17

Description

chsh in cPanel before 88.0.3 allows a Jailshell escape (SEC-497).

Frequently asked questions

What is CVE-2020-26100?: chsh in cPanel before 88.0.3 allows a Jailshell escape (SEC-497).
How severe is CVE-2020-26100?: CVE-2020-26100 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-26100 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26100?: CVE-2020-26100 affects Cpanel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-26100?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-26100 published?: CVE-2020-26100 was published on 2020-09-25 and last updated on 2026-06-17.

References

https://docs.cpanel.net/changelogs/88-change-log/

Affected products (1)

cpe:2.3:a:cpanel:cpanel:*:*:*:*:*:*:*:*

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